The present invention relates to automatic flush valve actuation devices for toilet and urinal facilities, and in particular to add-on flush valve operation devices that are adapted to be readily and easily attached to existing flush valve mechanisms for movement of the actuation handle of such flush valve mechanisms.
Public awareness of personal hygiene and water conservation issues has initiated a response by manufacturers of public and private sanitary and water use facilities to develop systems that eliminate human contact with environmental surfaces that may contain disease spreading bacteria and to minimize flush water usage to eliminate waste.
Many present toilet and urinal flush devices for sanitary facilities are operated by a water control valve including a manually operable flush handle adapted to be gripped and moved by a user following use of the sanitary facility. A typical valve arrangement is shown, by way of example, in U.S. Pat. Nos. 7,776,812 and 3,399,860. However, those valve actuation devices present several problems. Among these problems are the fact that with an enlightened awareness that public sanitary facilities may have been previously used by someone having a communicable or other disease that is spread upon contact, individual users of sanitary facilities are becoming reluctant to touch the flush handle and risk becoming ill. Therefore, the sanitary facility may remain unflushed, leaving human waste products in the toilet and urinal, obviously increasing the unsanitary conditions, and fouling the atmosphere in the facility. Therefore, having flush value mechanisms that people won't use can lead to extremely unsanitary and undesirable conditions.
In addition, many present flush handle operated valve mechanisms for sanitary devices are constructed such that the user can hold on to the handle for an excessive time period, retaining the valve mechanism in an open position longer than necessary to flush the toilet or urinal. This obviously wastes water, which can be a major problem in those parts of the world where water is a scarce commodity. Also, excessive water use leads to additional and unnecessary costs for the entity installing and maintaining the washroom facility.
Several systems have been developed in an attempt to address the hygiene arid water control problems of existing manual flush control mechanisms for sanitary facilities. These include structures which totally replace the manually operated flush valve mechanism with an automatic, sensor actuated flush valve operation device that is also connected to the 110 volt electrical system extant in the facility. Such a system is shown in U.S. Pat. No. 4,793,588. However, the replacement of existing manually operated flush handle devices with such units is costly, particularly in buildings such as hotels, office buildings and the like which presently have installed numerous manual handle operated flush mechanisms in their sanitary facilities. Such replacement would require the work of mechanical and plumbing personnel, and the installation cost of replacing numerous manually operable flush devices with automatic devices of the type disclosed in U.S. Pat. No. 4,793,588 would be prohibitive. Also, this replacement project would require a shut down of the water supply system or turning off water to the valve until the valve mechanisms could be replaced, which is undesirable in large hotels, offices and other structures. Additionally, building permits would be required for such a replacement project.
Another problem encountered with existing automatic, sensor actuated flush valve operation devices is that they must be installed on facilities having different heights. For example, the flush valve mechanism on a standard toilet is generally positioned lower than the flush valve mechanisms on toilets designed for use by disabled users. For such high mount facilities, the flush valve housing structures are about shoulder height of the user. Due to the placement of the sensor, when the device is mounted on a high mount facility, the sensor may be oriented at an angle that fails to respond to use of the facility and the facility may remain unflushed.
Another attempt to automatically operate a manual flush valve mechanism for a sanitary facility is shown in U.S. Pat. No. 3,056,143, which discloses a door operated electrical solenoid device for depressing a manual flush handle each time the door to the toilet stall is opened. However, the device shown in U.S. Pat. No. 3,056,143 has many shortcomings. The existing valve housing in the prior art structure would have to be disassembled, reworked and retrofitted to accept the bracket supporting the solenoid. This requires reconstruction of the valve housing. Also, the cantilever nature of the reference mounting structure will result in possible movement of the bracket upon actuation of the solenoid, and improper actuation of the flush handle. Further, the reference device is tied to the electrical system of the building in which the stall is located, requiring added installation costs. The reference device will operate each time the door opens, whereby the flush mechanisms will operate twice for each use. This waste of water could be significant, considering that sanitary facilities are operated 4,000 times per month in many installations. Additionally, in the reference device, the existing flush handle remains exposed, whereby the handle can be manually operated or kicked, as some users are prone to do to avoid touching the handle. This exposure of the handle can also lead to water waste through manual operation.
When designing a device that will automatically operate a flush handle of all existing manual flush apparatus, an important consideration is that as line water pressure increases, the handle stroke of a common flush valve must pivotally extend further from its initial position to actually flush the toilet. For example, flushing may occur with the handle pivoted one-half way through its full extent at a water pressure of 50 psi, but maybe required to be pivoted through 90 percent of its full motion to accomplish flushing at 100 psi. It has been determined that to provide proper flushing facing these variances in handle position, it is necessary to drive the handle to its full movable position, or to a metal-to-metal stop position if no buffer material is placed between the handle and the part of the valve housing through which the handle extends, to ensure that flushing occurs at high water pressures. Due to manufacturing tolerances, the “full down,” “full stop,” or “metal-to-metal stop” position of the handle varies somewhat between sanitary installations. If the valve operating mechanism is constructed to insure that a flush will occur at a “full down” position on one valve installation, this “full down” position may be beyond the “full down” position of another valve. In this situation, the motor driven cam or other drive mechanism will stall due to “metal-to-metal” contact between the valve handle and the valve housing before the cam has completed a full rotation. Therefore, the cam drive system for the handle must provide a degree of flexure, or “give,” to allow for this difference in valve handle operating parameters.
Therefore, it is an object of the present invention to provide an automatic flush valve actuation apparatus that can be installed and mounted on existing manual flush valve mechanisms without requiring any mechanical work or structural changes to the existing manual flush mechanism.
It is a further object of the present invention to provide an automatic flush valve actuation apparatus which can be readily mounted to existing flush valve mechanisms, whereby the rush valve actuation apparatus engages a portion of the flush mechanism housing to prevent rotation of the actuation apparatus during operation.
Another object of the present invention is to provide a battery operated flush valve actuation device for a sanitary unit such as a toilet or urinal, which requires no connection to the extant electrical system of the installation in which the sanitary unit is located.
An additional object of the present invention is to provide an automatically operated actuation device for existing sanitary unit flush handle mechanisms which can be actuated by sensors responsive to use of the facility, and by timing devices that automatically actuate the flush handle at predetermined time intervals.
Another object of the present invention is to provide an automatically operated actuation device for existing sanitary unit flush handle mechanisms which can be actuated by sensors responsive to use of the facility, the automatically operated actuation device capable of being mounted on the existing flush valve housing structure at an angle, such that the sensors are responsive to both low and high mount facilities.
Yet another object of the present invention is to provide an automatically operated flush valve handle actuation device in a compact, self contained unit which can readily be attached to an existing manual flush valve mechanism on existing sanitary units without the need to connect the actuation device to any outside power or control sources.
A further object of the present invention is to provide a compact self contained flush valve handle actuation device which is automatically mounted on and aligned with the existing flush valve housing structure, whereby the mounting structure provides the necessary torque to enable the operating mechanism inside the flush handle actuation device to overcome the valve housing spring pressure acting on the flush handle and to depress the flush handle to accomplish flushing.
Another object of the present invention is to provide flexure in the valve handle drive mechanism to prevent the handle drive cam or other drive mechanism from stalling when the handle reaches its “full down” or “metal-to-metal stop” position.
Another object of the present invention is to provide a compact, battery operated self contained flush valve handle actuation device that operates on minimum power drain of the batteries, and thus provides long battery life.
Another object of the present invention is to provide a compact self contained flush valve handle actuation device which can be adapted to mount and align with a variety of existing flush valve housing structures.